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Melatonin receptors play important roles in the regulation of circadian and seasonal rhythms, sleep, retinal functions, the immune system, depression, and type 2 diabetes development. Melatonin receptors are approved drug targets for insomnia, non‐24‐hour sleep‐wake disorders, and major depressive disorders. In mammals, two melatonin receptors (MTRs) exist, MT1 and MT2, belonging to the G protein‐coupled receptor (GPCR) superfamily. Similar to most other GPCRs, reliable antibodies recognizing melatonin receptors proved to be difficult to obtain. Here, we describe the development of the first monoclonal antibodies (mABs) for mouse MT1 and MT2. Purified antibodies were extensively characterized for specific reactivity with mouse, rat, and human MT1 and MT2 by Western blot, immunoprecipitation, immunofluorescence, and proximity ligation assay. Several mABs were specific for either mouse MT1 or MT2. None of the mABs cross‐reacted with rat MTRs, and some were able to react with human MTRs. The specificity of the selected mABs was validated by immunofluorescence microscopy in three established locations (retina, suprachiasmatic nuclei, pituitary gland) for MTR expression in mice using MTR‐KO mice as control. MT2 expression was not detected in mouse insulinoma MIN6 cells or pancreatic beta‐cells. Collectively, we report the first monoclonal antibodies recognizing recombinant and native mouse melatonin receptors that will be valuable tools for future studies.  相似文献   
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Background & Aims: Impaired message-structure mapping results in deficits in both sentence production and comprehension in aphasia. Structural priming has been shown to facilitate syntactic production for persons with aphasia (PWA). However, it remains unknown if structural priming is also effective in sentence comprehension. We examined if PWA show preserved and lasting structural priming effects during interpretation of syntactically ambiguous sentences and if the priming effects occur independently of or in conjunction with lexical (verb) information.

Methods & Procedures: Eighteen PWA and 20 healthy older adults (HOA) completed a written sentence-picture matching task involving the interpretation of prepositional phrases (PP; the chef is poking the solider with an umbrella) that were ambiguous between high (verb modifier) and low attachment (object noun modifier). Only one interpretation was possible for prime sentences, while both interpretations were possible for target sentences. In Experiment 1, the target was presented immediately after the prime (0-lag). In Experiment 2, two filler items intervened between the prime and the target (2-lag). Within each experiment, the verb was repeated for half of the prime-target pairs, while different verbs were used for the other half. Participants’ off-line picture matching choices and response times were measured.

Results: After reading a prime sentence with a particular interpretation, HOA and PWA tended to interpret an ambiguous PP in a target sentence in the same way and with faster response times. Importantly, both groups continued to show this priming effect over a lag (Experiment 2), although the effect was not as reliable in response times. However, neither group showed lexical (verb-specific) boost on priming, deviating from robust lexical boost seen in the young adults of prior studies.

Conclusions: PWA demonstrate abstract (lexically-independent) structural priming in the absence of a lexically-specific boost. Abstract priming is preserved in aphasia, effectively facilitating not only immediate but also longer-lasting structure-message mapping during sentence comprehension.  相似文献   

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Introduction   QT interval prolongation may cause the potentially lethal tachyarrhythmia torsades de pointes ( 1 ). The cause of the QT interval prolongation may be a congenital mutation in genes encoding cardiac potassium and sodium channels ( 2 ) or be acquired following drug administration ( 3 ) or metabolic disorders ( 4 ). Among a few other drugs volatile anaesthetics prolong the QT interval. During the last few years sevoflurane has become the most used volatile anaesthetic for the induction of anaesthesia in infants.
Methods   This investigation, on infants aged from 1 to 6 months, was approved by the institutional ethic committee. Thirty-six otherwise healthy infants due to elective surgery were included in our study The patients were randomly assigned to one of two treatment groups. Group S ( n  = 24) was anaesthetised with sevoflurane, Group H was anaesthetised with halothane. ECG recordings were taken before the anaesthesia onset, 15 min after the first contact with the volatile anaesthetic and 60 min after the ending of the volatile gas exposition. QTc interval was calculated using the Bazett's formula ( 5 ).
Results   QTc interval was significantly ( P < 0.0002) (Table 1) lengthened 15 min after anaesthesia induction with sevoflurane as well as 60 min ( P < 0.01) after the ending of the gas exposition without any difference in age and gender. The QTc interval in patients anaesthetised with halothane did not show any significant change.  

  Table 1  相似文献   

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Mechanism of bronchodilator effect in chronic airflow limitation.   总被引:1,自引:0,他引:1       下载免费PDF全文
OBJECTIVE: To examine the mechanisms through which two bronchodilators (theophylline and salbutamol) influence dyspnea during daily activities. METHODS: Twenty-four patients with chronic airflow limitation participated in a multiple crossover, randomized, placebo-controlled trial. The effect of theophylline and salbutamol, alone or combined, on pulmonary function and dyspnea during daily activities was examined. Correlations of changes in forced expiratory volume in 1 second (FEV1) and maximum expiratory pressures (MIPs) (independent variables) and changes in dyspnea score during daily activities (dependent variable) were also examined. RESULTS: The two drugs proved to be beneficial the effects in general were additive rather than synergistic. The drugs improved the FEV1; theophylline significantly improved the MIPs. The correlation between the changes in FEV1 and those in dyspnea score, after adjustment for the changes in MIPs, was 0.55 (p less than 0.001). The correlation between the changes in MIPs and those in dyspnea score, after adjustment for the changes in FEV1, was 0.39 (p less than 0.001). CONCLUSIONS: Changes in airway calibre and in respiratory muscle strength play an independent and important role in dyspnea during daily activities in patients with chronic airflow limitation. Changes in airway calibre may be of greater importance.  相似文献   
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